Closure meaning: And here comes the

And here comes the closure part: The closure of a lambda expression is this particular set of symbols defined in the outer context (environment) that give values to the free symbols in this expression, making them non-free anymore. But I honestly like the Closure + Closure ::fromCallable approach, because string or array as callable has always been weird. Will B. Over a year ago @RoboRobok one reason for requiring only Closure (anonymous function) as opposed to callable, would be to prevent access beyond the scope of the called function. After I read "A closure is a function that captures the bindings of free variables in its lexical context" and only understood the word 'function' in the sentence, I was very happy to find Justin Etheredge article whom author deserves a prize for explaining this using a simple and funny wording. Closure is the end or the closing down of something . It can be physical — like the closure of your local library — or emotional, like the closure you experience when you finally come to terms with the end of a romance.